blob: 27a63a0155ce598fe1a62077795f1f038ad3880e [file] [log] [blame]
* CXL Flash Device Driver
* Written by: Manoj N. Kumar <>, IBM Corporation
* Matthew R. Ochs <>, IBM Corporation
* Copyright (C) 2015 IBM Corporation
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
/* RHT - Resource Handle Table */
#define MC_RHT_NMASK 16 /* in bits */
#define MC_CHUNK_SHIFT MC_RHT_NMASK /* shift to go from LBA to chunk# */
#define HIBIT (BITS_PER_LONG - 1)
* LXT - LBA Translation Table
* +-------+-------+-------+-------+-------+-------+-------+---+---+
* +-------+-------+-------+-------+-------+-------+-------+---+---+
* The LXT Entry contains the physical LBA where the chunk starts (RLBA_BASE).
* AFU ORes the low order bits from the virtual LBA (offset into the chunk)
* with RLBA_BASE. The result is the physical LBA to be sent to storage.
* The LXT Entry also contains an index to a LUN TBL and a bitmask of which
* outgoing (FC) * ports can be selected. The port select bit-mask is ANDed
* with a global port select bit-mask maintained by the driver.
* In addition, it has permission bits that are ANDed with the
* RHT permissions to arrive at the final permissions for the chunk.
* LXT tables are allocated dynamically in groups. This is done to avoid
* a malloc/free overhead each time the LXT has to grow or shrink.
* Based on the current lxt_cnt (used), it is always possible to know
* how many are allocated (used+free). The number of allocated entries is
* not stored anywhere.
* The LXT table is re-allocated whenever it needs to cross into another group.
#define LXT_GROUP_SIZE 8
#define LXT_NUM_GROUPS(lxt_cnt) (((lxt_cnt) + 7)/8) /* alloc'ed groups */
#define LXT_LUNIDX_SHIFT 8 /* LXT entry, shift for LUN index */
#define LXT_PERM_SHIFT 4 /* LXT entry, shift for permission bits */
struct ba_lun_info {
u64 *lun_alloc_map;
u32 lun_bmap_size;
u32 total_aus;
u64 free_aun_cnt;
/* indices to be used for elevator lookup of free map */
u32 free_low_idx;
u32 free_curr_idx;
u32 free_high_idx;
u8 *aun_clone_map;
struct ba_lun {
u64 lun_id;
u64 wwpn;
size_t lsize; /* LUN size in number of LBAs */
size_t lba_size; /* LBA size in number of bytes */
size_t au_size; /* Allocation Unit size in number of LBAs */
struct ba_lun_info *ba_lun_handle;
/* Block Allocator */
struct blka {
struct ba_lun ba_lun;
u64 nchunk; /* number of chunks */
struct mutex mutex;
#endif /* ifndef _CXLFLASH_SUPERPIPE_H */